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    Subject[PATCH v5 mips-next 0/9] MIPS: vmlinux.lds.S sections fixes & cleanup
    This series hunts the problems discovered after manual enabling of
    ARCH_WANT_LD_ORPHAN_WARN. Notably:
    - adds the missing PAGE_ALIGNED_DATA() section affecting VDSO
    placement (marked for stable);
    - stops blind catching of orphan text sections with .text.*
    directive;
    - properly stops .eh_frame section generation.

    Compile and runtime tested on MIPS32R2 CPS board with no issues
    using two different toolkits:
    - Binutils 2.35.1, GCC 10.2.1 (with Alpine patches);
    - LLVM stack: 11.0.0 and from latest Git snapshot.

    Since v4 [3]:
    - new: drop redundant .text.cps-vec creation and blind inclusion
    of orphan text sections via .text.* directive in vmlinux.lds.S;
    - don't assert SIZEOF(.rel.dyn) as it's reported that it may be not
    empty on certain machines and compilers (Thomas);
    - align GOT table like it's done for ARM64;
    - new: catch UBSAN's "unnamed data" sections in generic definitions
    when building with LD_DEAD_CODE_DATA_ELIMINATION;
    - collect Reviewed-bys (Kees, Nathan).

    Since v3 [2]:
    - fix the third patch as GNU stack emits .rel.dyn into VDSO for
    some reason if .cfi_sections is specified.

    Since v2 [1]:
    - stop discarding .eh_frame and just prevent it from generating
    (Kees);
    - drop redundant sections assertions (Fangrui);
    - place GOT table in .text instead of asserting as it's not empty
    when building with LLVM (Nathan);
    - catch compound literals in generic definitions when building with
    LD_DEAD_CODE_DATA_ELIMINATION (Kees);
    - collect two Reviewed-bys (Kees).

    Since v1 [0]:
    - catch .got entries too as LLD may produce it (Nathan);
    - check for unwanted sections to be zero-sized instead of
    discarding (Fangrui).

    [0] https://lore.kernel.org/linux-mips/20210104121729.46981-1-alobakin@pm.me
    [1] https://lore.kernel.org/linux-mips/20210106200713.31840-1-alobakin@pm.me
    [2] https://lore.kernel.org/linux-mips/20210107115120.281008-1-alobakin@pm.me
    [3] https://lore.kernel.org/linux-mips/20210107123331.354075-1-alobakin@pm.me

    Alexander Lobakin (9):
    MIPS: vmlinux.lds.S: add missing PAGE_ALIGNED_DATA() section
    MIPS: CPS: don't create redundant .text.cps-vec section
    MIPS: vmlinux.lds.S: add ".gnu.attributes" to DISCARDS
    MIPS: properly stop .eh_frame generation
    MIPS: vmlinux.lds.S: explicitly catch .rel.dyn symbols
    MIPS: vmlinux.lds.S: explicitly declare .got table
    vmlinux.lds.h: catch compound literals into data and BSS
    vmlinux.lds.h: catch UBSAN's "unnamed data" into data
    MIPS: select ARCH_WANT_LD_ORPHAN_WARN

    arch/mips/Kconfig | 1 +
    arch/mips/include/asm/asm.h | 18 ++++++++++++++++++
    arch/mips/kernel/cps-vec.S | 1 -
    arch/mips/kernel/vmlinux.lds.S | 11 +++++++++--
    include/asm-generic/vmlinux.lds.h | 6 +++---
    5 files changed, 31 insertions(+), 6 deletions(-)

    --
    2.30.0


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